Remove javadoc warnings

We should remove the javadoc warnings in the build.

Guidance

If you would like to help, please select a sub-issue and comment on the issue, so that it can be assigned to you. There is no need to wait for a reply if you were the first person to request the issue, then it is yours and you can work on it and send a pull request.

Finding javadoc warnings

You can find the compiler warnings by running the javadoc command for the module you are working on. For example, if you are working on spring-security-core you can run:

./gradlew --no-build-cache clean :spring-security-core:javadoc

Look through the output for any warnings specific to that module (it may cause other modules to build too).

Perform checks

Ensure to perform checks after updating the Javadoc to ensure that things like checkstyle and formatting are still valid

Configure Error on Warning

After you have fixed the warnings, configure the module to error on warning. The first project should create a new Pre-compiled Script Plugin at buildSrc/src/main/groovy/javadoc-warnings-error.gradle that configures the javadoc (for java and kotlin) to fail on warnings. Subsequent projects should just apply this plugin.

Questions

If you have questions, feel free to reach out on your specific issue. We will update the instructions as we go.

Select a sub-issue and run ./gradlew --no-build-cache clean :spring-security-core:javadoc, replacing the module with the one you are working on. Read the warnings for that module, update the relevant Javadoc, and run the module checks for formatting and checkstyle. Done means its warnings are fixed and the module is configured to error on warnings through buildSrc/src/main/groovy/javadoc-warnings-error.gradle or the existing plugin.